The earlier known sweepers have separate adjusted support wheels and separate adjusted flap constructions in front of the rotatable brush and also some types have it moreover behind the brush. The height of the brush from the cleaned surface is adjusted and maintained by means of the support wheels. The position of said wheels in relation to the frame of the machine can be changed. By said height adjustment different contact areas can be achieved i.e. the contact length in the surface in the working direction of the brush can be adjusted larger or smaller.
The rotating brush in use easily transports light particles around it and may be back to the cleaned surface. In order to prevent this drift, the flap arrangement in front of the brush is used to lead loose material out of the brush. Also similar construction behind the brush is used. When the brush wears, the separate brush wires becomes shorter and thus the brush diameter becomes smaller. It follows that the support wheels have to be lifted in relation to the frame and the flap arrangements have to be moved nearer the brush. The sweepers of earlier known types have inconvenient adjustments separately for support wheels and flaps. The present invention provided for eliminating this disadvantage.